Metal film deposition apparatus

Abstract

To make it possible to accurately deposit a metallic film with a predetermined pattern using a masking material with a masking portion made of a rubber material.SOLUTION: A masking material 60 for a deposition apparatus 1 has a perforation 68 formed, and has a masking portion 65 made of a rubber material. On the opposite surface 65c facing a polymer electrolyte 13 among the surfaces of the masking portion 65, a contact prevention material 30 (coating sheet 30A) made of a resin material is arranged for preventing the masking portion 65 from contacting the polymer electrolyte 13.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to an apparatus for forming a metal film.

Background Art

[0002] Conventionally, a metal film is formed by depositing metal on the surface of a base material through electrolytic plating (for example, Patent Document 1). The film forming apparatus disclosed in Patent Document 1 includes a container (housing) that accommodates a plating solution. An opening is formed in the container, and the opening is sealed with an electrolyte membrane. The film forming apparatus further includes a pressing mechanism that presses the base material against the electrolyte membrane by the hydraulic pressure of the plating solution.

[0003] Here, when forming a metal film on the surface of a base material, a voltage is applied between an anode and the base material while pressing the base material with the hydraulic pressure of the electrolyte membrane. This enables formation of a metal film with a predetermined pattern on an underlayer. When forming a metal film with a predetermined pattern on a base material, it is also conceivable to use a masking material as shown in Patent Document 2.

Prior Art Literature

Patent Literature

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problem to be Solved by the Invention

[0005] However, when the mask portion of the masking material shown in Patent Document 2 is made of rubber, during film formation, when the masking material is pressed by the electrolyte membrane, fine rubber particles (rubber powder) from the mask portion adhere to the surface of the electrolyte membrane. When the electrolyte membrane stretches slightly due to the liquid pressure of the plating solution, it covers a portion of the perforations formed in the mask portion. As a result, during film formation, the movement of metal ions from the perforations toward the substrate is inhibited by the fine rubber particles adhering to the electrolyte membrane. This makes it difficult to form a metal film with a predetermined pattern corresponding to the shape of the perforations.

[0006] The present invention has been made in view of these points, and its object is to provide a metal film deposition apparatus that can accurately deposit a metal film of a predetermined pattern using a masking material having a mask portion made of rubber material. [Means for solving the problem]

[0007] In view of the above problems, the metal film deposition apparatus according to the present invention is a metal film deposition apparatus that deposits a metal film of a predetermined pattern on the surface of a substrate by electroplating, wherein the deposition apparatus comprises: a container having an opening formed at a position facing the substrate and containing a plating solution, the opening being covered with an electrolyte membrane; a pressing mechanism that presses the substrate with the electrolyte membrane by the liquid pressure of the plating solution contained in the container; an anode disposed inside the container at a position facing the electrolyte membrane; and a masking material disposed between the electrolyte membrane and the substrate, with a perforating portion of the predetermined pattern formed thereon, wherein the masking material has a mask portion made of rubber material with the perforating portion formed thereon, and a contact prevention material made of resin material is disposed on the surface of the mask portion facing the electrolyte membrane to prevent contact between the mask portion and the electrolyte membrane.

[0008] According to the present invention, during film formation, a masking material is brought into contact with the electrolyte membrane and the substrate, and the substrate is pressed by the electrolyte membrane through the masking material by the pressure of the plating solution contained in the container. In this state, when a voltage is applied between the anode and the substrate, metal ions contained in the plating solution contained in the container pass through the electrolyte membrane, and water in the plating solution seeps out from the electrolyte membrane as a seepage solution. As a result, the elastically deformed mask portion adheres closely to the surface of the substrate, and the seepage solution fills the perforations formed in the mask portion and is pressurized. In this state, metal ions in the plating solution pass through the perforations, and the passing metal ions become metal and precipitate on the surface of the substrate. As a result, a metal film with a predetermined pattern corresponding to the shape of the perforations can be formed on the surface of the substrate.

[0009] Here, even if the electrolyte membrane deforms toward the mask portion due to the liquid pressure of the plating solution, a contact prevention material made of resin material is placed on the surface of the mask portion that faces the electrolyte membrane, thus preventing the electrolyte membrane from coming into contact with the opposing surface of the mask portion. This prevents rubber particles derived from the rubber material of the mask portion from adhering to the electrolyte membrane. As a result, even if the electrolyte membrane deforms due to the liquid pressure of the plating solution, the portion of the electrolyte membrane covering the penetration portion of the mask portion does not hinder the movement of metal ions by rubber particles, so a metal film with a predetermined pattern can be formed with high precision.

[0010] In a more preferred embodiment, the contact prevention material is a covering sheet disposed on the opposing surface so as to cover the through portion, and the covering sheet has a plurality of openings formed therein at least in positions that cover the through portion, through which the plating solution is permeable.

[0011] In this embodiment, since the coating sheet is positioned on the opposing surface so as to cover the through-holes, it is possible to suppress the adhesion of rubber particles to the electrolyte membrane. In addition, since the coating sheet is positioned so as to cover the through-holes of the mask portion, it is possible to suppress the sagging of the electrolyte membrane that deforms due to the liquid pressure of the plating solution. Furthermore, the liquid pressure of the plating solution can be applied uniformly to the mask portion through the electrolyte membrane and the coating sheet. As a result, the deformation of the mask portion can be made uniform, and the sealing performance between the mask portion and the substrate can be stably ensured. Furthermore, since multiple openings that allow the plating solution to pass through are formed at least in positions that cover the through-holes, the seepage solution that seeps out from the electrolyte membrane passes through the openings in the coating sheet and is supplied to the through-holes. As a result, during film formation, metal ions move within the seepage solution that fills the through-holes, so that a metal film corresponding to the pattern of the through-holes can be stably formed on the surface of the substrate.

[0012] In a more preferred embodiment, the mask portion comprises a first portion facing the electrolyte membrane and a second portion facing the substrate, the masking material having a mesh portion woven with wire, the mesh portion being positioned between the first portion and the second portion and holding the first portion and the second portion.

[0013] In this embodiment, the mesh portion is sandwiched between the first portion facing the electrolyte membrane and the second portion facing the substrate, so that the force acting on the mesh portion due to the liquid pressure of the plating solution can be uniformly distributed to the second portion. As a result, the deformation of the second portion can be made uniform, and the sealing performance between the mask portion and the substrate can be stably ensured. Furthermore, since the mesh openings of the mesh portion are formed at the position of the through portion, the seepage liquid that seeps out from the electrolyte membrane passes through the mesh openings of the mesh portion. As a result, metal derived from metal ions can be stably deposited on the surface of the substrate. Since the first and second portions can be formed continuously through the mesh openings of the mesh portion, the mask portion can be stably held in place by the mesh portion.

[0014] In a more preferred embodiment, the covering sheet is a sheet made of a mesh woven with wire, and the openings of the mesh of the covering sheet are larger than the openings of the mesh portion.

[0015] According to this embodiment, since the mesh openings of the covering sheet are larger than the mesh openings of the mesh portion, the seepage liquid from the electrolyte membrane can be smoothly supplied from the openings of the covering sheet to the perforated portion of the mask. This makes it possible to form a metal film with a stable pattern.

[0016] In another preferred embodiment, the contact prevention material is a resin coating applied to the opposing surfaces.

[0017] According to this embodiment, since the resin film is applied to the opposing surface of the mask portion, it is possible to suppress the adhesion of rubber particles to the electrolyte membrane, and the seepage solution (plating solution) that seeps out from the electrolyte membrane is smoothly supplied to the perforations of the mask portion. As a result, a metal film with a desired pattern can be stably formed. [Effects of the Invention]

[0018] According to the present invention, a metal film with a predetermined pattern can be accurately formed using a masking material having a mask portion made of rubber material. [Brief explanation of the drawing]

[0019] [Figure 1] This is a schematic cross-sectional view showing an example of a metal film deposition apparatus according to an embodiment of the present invention. [Figure 2] Figure 1 is a schematic perspective view showing the coating sheet, the masking material, and the substrate on which the metal film has been deposited. [Figure 3] Figure 1 is a schematic cross-sectional view illustrating the film deposition process using the film deposition apparatus shown. [Figure 4]It is an enlarged cross-sectional view of a main part for explaining the formation of a metal film by the film forming apparatus shown in FIG. 3. [Figure 5] It is a schematic perspective view showing a modification of the masking material shown in FIG. 3. [Figure 6] It is an enlarged cross-sectional view of a main part for explaining the formation of a metal film using the film forming apparatus shown in FIG. 5. [Figure 7] It is an enlarged cross-sectional view for explaining the formation of a metal film using a masking material according to a comparative example.

Mode for Carrying Out the Invention

[0020] A metal film forming apparatus 1 according to an embodiment of the present invention will be described. FIG. 1 is a schematic cross-sectional view showing an example of the metal film forming apparatus according to the embodiment of the present invention.

[0021] As shown in FIG. 1, the film forming apparatus 1 is a film forming apparatus that forms a metal film F of a predetermined pattern P on a base material B by electrolytic plating in a state where a masking material 60 is sandwiched between an electrolyte membrane 13 and the base material B. Specifically, the film forming apparatus 1 includes an anode 11, an electrolyte membrane 13, and a power source 14 that applies a voltage between the anode 11 and the base material B.

[0022] The film forming apparatus 1 includes a container 15 that accommodates the anode 11 and a plating solution L, a mounting table 40 on which the base material B is mounted, and the masking material 60. During film formation, the masking material 60 is mounted on the mounting table 40 together with the base material B. The electrolyte membrane 13 is disposed between the masking material 60 and the anode 11.

[0023] The film forming apparatus 1 includes a linear motion actuator 70 that moves the container 15 up and down. In the present embodiment, for convenience of explanation, it is premised that the electrolyte membrane 13 is disposed below the anode 11, and the masking material 60 and the base material B are further disposed below the electrolyte membrane 13. However, as long as the metal film F can be formed on the surface of the base material B, the positional relationship is not limited thereto.

[0024] Substrate B functions as a cathode. Substrate B is a plate-shaped substrate. In this embodiment, substrate B is a rectangular substrate. Of the surfaces of substrate B, the surface facing the electrolyte film 13 (screen mask 62) is the film-forming surface that functions as a cathode. The material of substrate B is not particularly limited as long as it functions as a cathode (i.e., a conductive surface). Substrate B may be made of a metallic material such as aluminum or copper.

[0025] In this embodiment, as shown in Figure 2, a pattern (wiring pattern) P is formed from a metal film F. Therefore, as the substrate B, a substrate is used in which an underlayer Bb of copper or the like is formed on the surface of an insulating substrate Ba such as resin. In this case, after the metal film F is formed, the underlayer Bb other than the area where the metal film F is formed is removed by etching or the like. This makes it possible to form a pattern P of metal film F on the surface of the insulating substrate Ba.

[0026] The anode 11 is, for example, a non-porous (e.g., non-porous) anode made of the same metal as the metal film. The anode 11 has a block-like or plate-like shape. Examples of materials for the anode 11 include copper. The anode 11 dissolves when a voltage is applied from the power supply 14. However, when forming a film using only metal ions from the plating solution L, the anode 11 is insoluble in the plating solution L. The anode 11 is electrically connected to the positive electrode of the power supply 14. The negative electrode of the power supply 14 is electrically connected to the substrate B via the mounting base 40.

[0027] The plating solution L is a liquid containing the metal to be formed into a metal film in an ionic state. Examples of such metals include copper, nickel, gold, silver, or iron. The plating solution L is a solution obtained by dissolving (ionizing) these metals with an acid such as nitric acid, phosphoric acid, succinic acid, sulfuric acid, or pyrophosphate. Examples of solvents for this solution include water and alcohol. For example, if the metal is copper, the plating solution L may be an aqueous solution containing copper sulfate, copper pyrophosphate, etc.

[0028] The electrolyte membrane 13 is a membrane that, when brought into contact with the plating solution L, can impregnate (contain) metal ions together with the plating solution L. The electrolyte membrane 13 is a flexible membrane. The material of the electrolyte membrane 13 is not particularly limited as long as the material allows metal ions from the plating solution L to move to the substrate B side when a voltage is applied by the power supply 14. Examples of materials for the electrolyte membrane 13 include ion-exchange resins such as fluororesins such as Nafion® manufactured by DuPont. The film thickness of the electrolyte membrane 13 is preferably in the range of 20 μm to 200 μm. More preferably, the film thickness is in the range of 20 μm to 60 μm.

[0029] The container 15 is made of a material insoluble in the plating solution L. The container 15 has a containment space 15a for containing the plating solution L. The anode 11 is placed in the containment space 15a of the container 15. An opening 15d is formed on the substrate B side of the containment space 15a. The opening 15d of the container 15 is covered with an electrolyte membrane 13. Specifically, the periphery of the electrolyte membrane 13 is sandwiched between the container 15 and the frame 17. This allows the plating solution L in the containment space 15a to be sealed with the electrolyte membrane 13.

[0030] As shown in Figures 1 and 3, the linear actuator 70 raises and lowers the housing 15 so that the electrolyte membrane 13 and the masking material 60 can move in and out of contact. In this embodiment, the mounting base 40 is fixed, and the housing 15 is raised and lowered by the linear actuator 70. The linear actuator 70 is an electrically operated actuator that converts the rotational motion of a motor into linear motion using a ball screw or the like (not shown). However, a hydraulic or pneumatic actuator may be used instead of an electrically operated actuator.

[0031] The housing 15 has a supply channel 15b for supplying the plating solution L to the housing space 15a. Furthermore, the housing 15 has a discharge channel 15c for discharging the plating solution L from the housing space 15a. The supply channel 15b and the discharge channel 15c are holes that communicate with the housing space 15a. The supply channel 15b and the discharge channel 15c are formed on either side of the housing space 15a. The supply channel 15b is fluidically connected to the liquid supply pipe 51. The discharge channel 15c is fluidically connected to the liquid discharge pipe 52.

[0032] The film deposition apparatus 1 further comprises a liquid tank 90, a liquid supply pipe 51, a liquid discharge pipe 52, and a pump 80. As shown in Figure 1, the liquid tank 90 contains the plating solution L. The liquid supply pipe 51 connects the liquid tank 90 to the housing 15. The pump 80 is provided on the liquid supply pipe 51. The pump 80 supplies the plating solution L from the liquid tank 90 to the housing 15. The liquid discharge pipe 52 connects the liquid tank 90 to the housing 15. The liquid discharge pipe 52 is provided on the pressure regulating valve 54. The pressure regulating valve 54 adjusts the pressure (liquid pressure) of the plating solution L in the housing space 15a to a predetermined pressure.

[0033] In this embodiment, the plating solution L is drawn from the liquid tank 90 into the liquid supply pipe 51 by driving the pump 80. The drawn-in plating solution L is then pumped from the supply channel 15b to the containment space 15a. The plating solution L in the containment space 15a is returned to the liquid tank 90 via the discharge channel 15c. In this way, the plating solution L circulates within the film deposition apparatus 1.

[0034] Furthermore, by continuously driving the pump 80, the liquid pressure of the plating solution L in the containment space 15a can be maintained at a predetermined pressure by the pressure regulating valve 54. The pump 80 presses the masking material 60 through the covering sheet 30A with the electrolyte membrane 13 on which the liquid pressure of the plating solution L acts. However, the pressing mechanism is not particularly limited as long as the electrolyte membrane 13 can press the masking material 60. Instead of the pump 80, an injection mechanism consisting of a piston and cylinder that injects the plating solution L may also be used.

[0035] The mounting base 40 is formed, for example, from a conductive material (e.g., metal). The mounting base 40 has a recess 41. The recess 41 is a portion recessed from the opposite surface of the mounting base 40 in order to accommodate the base material B.

[0036] The masking material 60 comprises a frame 61 and a screen mask 62. The frame 61 supports the peripheral edge 62a of the screen mask 62 on the electrolyte membrane 13 side relative to the frame 61. Specifically, the peripheral edge 62a of the screen mask 62 is fixed to the frame 61. In this embodiment, the screen mask 62 has a rectangular outer shape. Therefore, the frame 61 has a rectangular frame-like shape. The material of the frame 61 is not particularly limited as long as it can maintain the shape of the masking material 60. For example, the material of the frame 61 can be a metal material such as stainless steel, or a resin material such as thermoplastic resin. The frame 61 is formed, for example, from a metal plate by punching, and has a thickness of about 1 mm to 3 mm.

[0037] The screen mask 62 has through-portions 68 formed according to a predetermined pattern P of the metal film F. The screen mask 62 comprises a mesh portion 64 and a mask portion 65. The screen mask 62 is a mask with flexibility ranging from approximately 50 μm to 400 μm. The screen mask 62 is supported on the surface of the frame 61, on the side facing the substrate B.

[0038] The periphery of the mesh portion 64 is fixed to the frame 61. The mesh portion 64 is stretched with a predetermined tension so as to cover the opening of the frame 61. The mesh portion 64 has multiple openings 64c, 64c, ... formed in a grid pattern. Specifically, as shown in Figure 4, the mesh portion 64 consists of a mesh-like portion (mesh) in which multiple oriented wires 64a, 64b are woven together so as to intersect. Multiple wires 64a, 64a are arranged with gaps between them, and multiple intersecting wires 64b, 64b are also arranged with gaps between them. As a result, multiple openings 64c, 64c, ... are formed in a grid pattern in the mesh portion 64. The material of the wires 64a, 64b is not particularly limited as long as it has corrosion resistance to the plating solution L. Examples of materials for the wires 64a, 64b include resin materials such as polyester resin. In addition, the mesh portion 64 may be made of any resin material that can form a wire, such as acrylic resin, vinyl acetate resin, polyvinyl chloride resin, polypropylene resin, polyethylene resin, polystyrene resin, polycarbonate resin, polyimide resin, or urethane resin.

[0039] The mask portion 65 is held by a sheet-like mesh portion 64. The mask portion 65 has through-portions 68 formed according to a predetermined pattern P. The mask portion 65 is the part that adheres to the substrate B during film formation due to pressure from the electrolyte membrane 13. The material of the mask portion 65 is not particularly limited as long as it can adhere to the substrate B. For example, the material of the mask portion 65 can be a rubber material such as silicone rubber (PMDS) or ethylene propylene diene rubber (EPDM). The hardness of the rubber material is preferably HS100 or less on the Shore A hardness scale, and more preferably HS50 or less.

[0040] The mask portion 65 is made of an elastic material that undergoes compressive elastic deformation upon pressure from the electrolyte membrane 13. To ensure adhesion with the substrate B, the amount of deformation of the mask portion 65 in the thickness direction (pressure direction) due to pressure from the electrolyte membrane 13 may be in the range of 5 to 20% of the thickness of the mask portion before deformation. A screen mask 62 having a predetermined pattern P can be manufactured using general silkscreen manufacturing techniques using emulsions. Therefore, a detailed explanation of the manufacturing method of the screen mask 62 is omitted.

[0041] As shown in Figure 4, the mask portion 65 comprises a first portion 65a facing the electrolyte membrane 13 and a second portion 65b facing the substrate B. The mesh portion 64 is positioned between the first portion 65a and the second portion 65b and is the portion that holds the first portion 65a and the second portion 65b. That is, the mesh portion 64 is sandwiched between the first portion 65a and the second portion 65b, and the first portion 65a and the second portion 65b are connected through the opening 64c of the mesh portion 64. The force acting on the mesh portion 64 due to the liquid pressure of the plating solution L during film formation can be uniformly distributed to the second portion 65b. As a result, the deformation of the second portion 65b can be made uniform, and the sealing performance between the mask portion 65 and the substrate B can be stably ensured.

[0042] Furthermore, a covering sheet 30A is placed on the surface 65c of the mask portion 65 that faces the electrolyte membrane 13, to prevent contact between the mask portion 65 and the electrolyte membrane 13. The covering sheet 30A corresponds to the "contact prevention material" as defined in the present invention. In this embodiment, the covering sheet 30A is preferably flexible, and its configuration is not limited as long as it can supply the plating solution L seeping from the electrolyte membrane 13 to the through portion 68 of the mask portion 65. It may also be a resin (resin material) sheet material with openings formed according to the shape of the pattern P of the through portion 68. In this embodiment, the covering sheet 30A has a plurality of openings 31c that allow the plating solution L to pass through, at least in positions that cover the through portion 68. Examples of such a covering sheet 30A include a resin sponge-like sheet or a resin sheet with a plurality of openings (through holes). Since the resin material is a synthetic resin manufactured by polymerization reaction or the like, fine particles do not adhere to the electrolyte membrane 13. Examples of such resin materials include acrylic resin, vinyl acetate resin, polyvinyl chloride resin, polypropylene resin, polyethylene resin, polystyrene resin, polycarbonate resin, polyimide resin, urethane resin, or polyester resin. In addition, super engineering plastics such as liquid crystal polymers may also be used.

[0043] The covering sheet 30A is preferably a sheet made of a mesh woven with wires 31a and 31b. The covering sheet 30A has a grid of multiple openings 31c, 31c, ... formed in a grid pattern. Specifically, as shown in Figures 2 and 4, the covering sheet 30A consists of a mesh portion in which multiple oriented wires 31a and 31b are woven together so as to intersect. Multiple wires 31a and 31b are arranged with gaps between them, and multiple intersecting wires 31b and 31b are also arranged with gaps between them. As a result, multiple openings 31c, 31c, ... are formed in a grid pattern in the covering sheet 30A. The material of the wires 31a and 31b is the resin material described above. The openings 31c of the mesh of the covering sheet 30A are larger than the openings of the mesh of the mesh portion 64. Specifically, the spacing between wires 31a, 31a (wires 32a, 32a) is greater than the spacing between wires 64a, 64a (64b, 64b).

[0044] A film deposition method using the film deposition apparatus 1 will be described with reference to Figures 1 to 4. First, a placement step is performed. In this step, as shown in Figure 1, the substrate B is placed on the mounting table 40. Specifically, the substrate B is placed in the recess 41 of the mounting table 40. In this embodiment, with the substrate B placed in the recess 41, the surface of the substrate B protrudes from the opposing surface of the mounting table 40 (the surface facing the electrolyte membrane 13). This allows the mask portion 65 of the masking material 60 to make uniform contact with the surface of the substrate B. At this time, the alignment of the substrate B with respect to the anode 11 attached to the housing 15 may be adjusted, and the temperature of the substrate B may be adjusted.

[0045] Next, the masking material 60 is placed on the mounting base 40. At this time, the masking material 60 is housed so that the surface of the base material B is contained within the internal space 69 of the frame 61 of the masking material 60. Specifically, as shown in Figure 4, the surface of the base material B (the surface of the underlayer Bb) is covered with the mask portion 65 of the masking material 60. Furthermore, as shown in Figure 2, the covering sheet 30A is placed so as to cover the opposing surface 65c of the mask portion 65.

[0046] Next, a pressing process is performed. In this process, the electrolyte membrane 13 presses the substrate B through the coating sheet 30A and the screen mask 62 using the liquid pressure of the plating solution L in contact with the electrolyte membrane 13. First, the linear actuator 70 is driven. This lowers the housing 15 toward the coating sheet 30A and the masking material 60 from the state shown in Figure 1 to the state shown in Figure 3.

[0047] Next, the pump 80 is driven. This supplies the plating solution L to the containment space 15a of the containment body 15. Since the liquid discharge pipe 52 is equipped with a pressure regulating valve 54, the liquid pressure of the plating solution L in the containment space 15a is maintained at a predetermined pressure. As a result, as shown in Figure 4, the liquid pressure of the plating solution L causes the electrolyte membrane 13 to deform toward the internal space 69 of the frame 61, allowing the screen mask 62 to be sandwiched between the electrolyte membrane 13 and the substrate B. Furthermore, the liquid pressure of the plating solution L acts on the electrolyte membrane 13, which can press down on the masking material 60.

[0048] As shown in Figure 4, this pressure allows the screen mask 62 to adhere tightly to the surface of the substrate B. Since the mask portion 65 is made of rubber material, the pressure of the plating solution L causes the mask portion 65 to compress and elastically deform, improving the adhesion between the mask portion 65 and the substrate B. Furthermore, if the pressure on the electrolyte membrane 13 is sustained, the perforations 68 formed in the screen mask 62 are filled with seepage liquid (plating solution) La that has seeped out from the electrolyte membrane 13, which has swollen with the plating solution L, and pressurized.

[0049] Next, as shown in Figure 4, a film formation process is performed. In this process, the pressing state by the electrolyte membrane 13 from the pressing process is maintained, and a metal film F is formed. Specifically, a voltage is applied between the anode 11 and the substrate B. This causes the metal ions contained in the plating solution L to pass through the electrolyte membrane 13. The metal ions that have passed through the electrolyte membrane 13 move to the surface of the substrate B via the seepage solution La and are reduced on the surface of the substrate B. As a result, the metal ions in the plating solution L pass through the through-holes 68, and the passing metal ions are deposited on the surface of the substrate B. In this way, as shown in Figure 2, a metal film F with a predetermined pattern P corresponding to the shape of the through-holes 68 can be formed on the surface of the substrate B.

[0050] Incidentally, in a film deposition apparatus, if a coating sheet 30A is not used as a contact prevention material, as shown in Figure 7, the mask portion 65 is directly pressed by the electrolyte membrane 13 during film deposition, causing rubber microparticles C from the mask portion 65 to adhere to the surface of the electrolyte membrane 13. When the electrolyte membrane 13 stretches slightly due to the liquid pressure of the plating solution L, the portion of the electrolyte membrane 13 to which the rubber microparticles C have adhered deforms so that it enters the through-holes 68 formed in the mask portion 65. As a result, during film deposition, the movement of metal ions from the through-holes 68 toward the substrate B is inhibited by the rubber microparticles C attached to the electrolyte membrane 13. This makes it difficult to deposit a metal film F with a predetermined pattern P corresponding to the shape of the through-holes 68, as shown in Figure 7. In particular, when the metal film F is deposited repeatedly, this phenomenon becomes more pronounced because the electrolyte membrane 13 stretches due to repeated liquid pressure.

[0051] However, in this embodiment, as shown in Figure 4, a coating sheet (contact prevention material) 30A made of resin material is placed on the opposing surface 65c of the mask portion 65 that faces the electrolyte membrane 13. As a result, even if the electrolyte membrane 13 deforms toward the mask portion 65 due to the liquid pressure of the plating solution L, it is possible to avoid the electrolyte membrane 13 directly contacting the opposing surface 65c of the mask portion 65. This prevents rubber particles derived from the rubber material of the mask portion 65 from adhering to the electrolyte membrane 13. As a result, even if the electrolyte membrane 13 deforms due to the liquid pressure of the plating solution L, there is no obstruction of metal ion movement by rubber particles in the portion of the electrolyte membrane 13 that covers the penetrating portion 68 of the mask portion 65. For this reason, compared to the case shown in Figure 7, a metal film F with a predetermined pattern P can be formed on the substrate B with high precision.

[0052] In particular, in this embodiment, since the covering sheet 30A is positioned to cover the through-hole 68 of the mask portion 65, it is possible to suppress sagging of the electrolyte membrane 13 which deforms due to the liquid pressure of the plating solution L. Furthermore, the liquid pressure can be applied uniformly to the mask portion 65 via the electrolyte membrane 13 and the covering sheet 30A. As a result, the deformation of the mask portion 65 can be made uniform, and the sealing performance between the mask portion 65 and the substrate B can be stably ensured.

[0053] Furthermore, the coating sheet 30A has multiple openings that allow the plating solution L to pass through, positioned to cover the through-hole 68. 31 Since c is formed, the seepage liquid La (plating solution) that seeps out from the electrolyte membrane 13 is opened in the opening of the coating sheet 30A. 31 The material can pass through c and be stably supplied to the through-hole 68. As a result, a metal film F corresponding to the pattern of the through-hole 68 can be stably formed on the surface of the substrate B.

[0054] Furthermore, since the mesh openings 31c of the covering sheet 30A are larger than the mesh openings 64c of the mesh portion 64, the seepage liquid La that has seeped out from the electrolyte membrane 13 can be smoothly supplied from the openings of the covering sheet 30A to the perforations 68 of the mask portion 65. As a result, a metal film F corresponding to the pattern of the perforations 68 can be stably formed on the surface of the substrate B.

[0055] Subsequently, the linear actuator 70 raises the housing 15, separating the substrate B from the electrolyte membrane 13, and removing the substrate B from the mounting table 40. When manufacturing wiring with a metal film F, it is sufficient to etch the conductive underlayer Bb formed on the surface of the insulating substrate Ba of the substrate B, leaving the portion where the metal film F is formed intact.

[0056] A modified film deposition apparatus will be described below with reference to Figures 5 and 6. In the film deposition apparatus shown in Figures 1 to 4, a coating sheet 30A was used on the opposing surface facing the electrolyte membrane 13 as a contact prevention material to prevent contact between the mask portion 65 and the electrolyte membrane 13. In this modified apparatus, instead of the coating sheet 30A, a resin coating 30B is provided on the mask portion 65 as a contact prevention material.

[0057] In this embodiment, a resin film 30B made of a resin material (synthetic resin) is formed on the surface of the mask portion 65 so as to cover the opposing surface 65c facing the electrolyte membrane 13. The resin film 30B is preferably flexible and is formed on the opposing surface 65c of the mask portion 65 as follows. As one method of film formation, the resin film 30B may be formed on the opposing surface 65c of the mask portion 65 by applying an emulsion in which synthetic resin particles are dispersed in a liquid, for example, and then drying it. As another method of film formation, the resin film 30B may be formed on the opposing surface 65c of the mask portion 65 by applying an uncured resin to the opposing surface 65c of the mask portion 65 and then polymerizing the applied resin. As yet another method of film formation, the resin film 30B may be formed by attaching a resin film having through holes of the same shape as a predetermined pattern P to the opposing surface 65c of the mask portion 65.

[0058] Examples of resins for the resin coating 30B include fluororesins such as polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), or perfluoroalkoxy fluororesins (PFA). By using a fluororesin for the resin coating 30B, the friction of the surface of the resin coating 30B can be reduced. Therefore, even if the electrolyte membrane 13 presses against the mask portion 65 and stretches during repeated film formation, it is possible to prevent the electrolyte membrane 13 from being damaged by the resin coating 30B.

[0059] Alternatively, the resin used for the resin coating 30B can be a polyethylene resin such as polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT), or polyethylene naphthalate (PEN). By using a polyethylene resin for the resin coating 30B, the flexibility of the resin coating 30B can be increased. Therefore, even if the electrolyte membrane 13 presses against the mask portion 65 and stretches during repeated film formation, it is possible to prevent the electrolyte membrane 13 from being damaged by the resin coating 30B.

[0060] Even in this modified example, as shown in Figure 6, the resin film 30B is positioned on the opposing surface 65c of the mask portion 65, which prevents the rubber particles of the mask portion 65 from adhering to the electrolyte membrane 13. In addition, the seepage liquid La that has seeped out from the electrolyte membrane 13 is directly supplied to the through portion 68 of the mask portion 65. In this way, a metal film F with the desired pattern P can be stably formed. [Examples]

[0061] A mask portion was formed by creating perforations on both sides of a mesh portion made of LCP resin with a wire diameter of 20 μm and 420 mesh using silicone rubber. This produced a masking material having both a mesh portion and a masking portion. The thickness of the mask portion was 30 μm for the first portion and 20 μm for the second portion. The perforations had three different widths: 100 μm, 250 μm, and 500 μm. Next, a covering sheet of LCP resin mesh with a wire diameter of 20 μm and 420 mesh was prepared.

[0062] Next, a copper (Cu) substrate was prepared in the shape of a square with a thickness of 0.9 mm and a side length of 7.8 cm. The substrate was subjected to cathodic electrolytic degreasing at 55°C for 1 minute using an IC-200RM manufactured by JCU Corporation, and then the substrate was rinsed with pure water for 1 minute. Furthermore, the substrate was acid-washed by immersing it in 10% dilute sulfuric acid at room temperature for 1 minute, and then the substrate was rinsed with pure water for 1 minute.

[0063] Subsequently, as shown in Figure 4, a metal film with a thickness of 5 μm was deposited on the surface of the substrate by solid-phase electrodeposition (SED) using an apparatus with a configuration similar to that of the film deposition apparatus including the coating sheet. Specifically, before deposition, the masking material was pressurized with the coating sheet using an electrolyte membrane under a pressure of 0.6 MPa for 24 hours, and then the film was deposited under the following conditions: deposition temperature: 42°C, plating solution: 1 mol / l copper sulfate + 0.2 mol / l sulfuric acid, anode: phosphorus-containing copper plate, electrode distance between anode and cathode: 2 mm, pressure: 0.6 MPa, deposition area: 38 cm² 2 Circuit board size: 61.4cm 2 The current was 7ASD.

[0064] As a comparative example, as shown in Figure 7, film deposition was performed under the same conditions as in the example, but without the mesh used in the example. Defects in the films deposited in the example and the comparative example were checked. As a result, the metal film of the example had no defects, while the metal film of the comparative example had eight defects. Upon examination of the electrolyte membrane of the comparative example, it was found that fine rubber particles from the mask portion were attached, and this was the cause of the defects in the metal film.

[0065] Although embodiments of the present invention have been described in detail above, the present invention is not limited to the embodiments described above, and various design modifications can be made without departing from the spirit of the invention as described in the claims. [Explanation of Symbols]

[0066] 1: Film deposition apparatus, 11: Anode, 13: Electrolyte membrane, 30A: Coating sheet (contact prevention material), 30B: Resin coating (contact prevention material), 60: Masking material, 61: Frame, 62: Screen mask, 64: Mesh part, 65: Mask part, 65a: First part, 65b: Second part, 65c: Opposing surface, 68: Through part, B: Substrate, F: Metal coating, L: Plating solution

Claims

1. A metal film deposition apparatus for depositing a metal film with a predetermined pattern onto the surface of a substrate by electroplating, The aforementioned film deposition apparatus is A container having an opening formed at a position opposite to the substrate, containing a plating solution, and the opening covered with an electrolyte membrane, A pressing mechanism that presses the substrate with the electrolyte membrane by the liquid pressure of the plating solution contained in the container, Inside the container, an anode is positioned opposite the electrolyte membrane, The system comprises a masking material disposed between the electrolyte membrane and the substrate, having a predetermined pattern of penetrating portions formed thereon, The masking material has the through portion formed therein and a mask portion made of rubber material, On the surface of the mask portion that faces the electrolyte membrane, a contact prevention material made of a resin material is placed to prevent contact between the mask portion and the electrolyte membrane. The contact prevention material is a covering sheet that is placed on the opposing surface so as to cover the penetrating portion. The covering sheet has a plurality of openings formed in positions that allow the plating solution to pass through, at least in positions that cover the through-portion. The mask portion comprises a first portion facing the electrolyte membrane and a second portion facing the substrate. A metal film deposition apparatus comprising a masking material having a mesh portion woven with wire, wherein the mesh portion is positioned between the first portion and the second portion and holds the first portion and the second portion.

2. The aforementioned covering sheet is a sheet made of a mesh woven with wires, The metal film forming apparatus according to claim 1, wherein the openings of the mesh of the covering sheet are larger than the openings of the mesh portion.

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